DIY rotary DJ mixer

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Here's a top shot of the build so far:

 

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Tested the knob scheme, added DC jack/power to the mic pre and wired the PFL/cue select switch :

 

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Wired the channels into the summing bus, added a headphone vol knob and a master vol :

Here's a pic of the front panel :

EDIT : there's still the master EQ to do and a headphone jack plus some wiring.. other than that it's about 80% done.

 

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Added the master EQ today, kind of tight in there but I managed to solder it nevertheless :

Here's a pic of the front panel with the EQ in place :

 

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Wired a headphone out and tested both stereo channels, seems to be working.. also PFL and the EQ. The EQ sounds awesome with a crossover frequency at around 120Hz according to my calculations.

The only downside is that the 100k pots are too high resistance so only 1/4 of the taper is useable.

EDIT : there's still the main outs to wire.. other than that it's done.

 

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Wired the master outs, it's now finished:

Also labeled the front panel:

 

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Eyeing on my next build, I measured a smartphone pgm output to be completely muted with the channel potentiometer at 57,3kOhm.. would a 10kOhm summing resistor (series) and a 50kOhm dual log pot do the trick?

I haven't measured with a CD player but I suspect they have higher output (a CDJ-800 overloaded the preamp ins of my first build).. use a 25kOhm trim perhaps?

EDIT : there's the EQ circuitry in the signal path which I didn't take into account.. I measured the HF series caps as having 290R resistance (the LF has 220R resistors) with a multimeter, is this the correct way to measure them? Iirc parallel resistance is calculated as 1/R1 + 1/R2 etc.. or ape the EQ circuitry in the new build to compensate (the input to output resistance was ~57,4kOhm)